SEATTLE -- Seattle Mariners starter Hisashi Iwakuma helped continue Houston's offensive struggles Monday night, and the Astros didn't help themselves with their play in the field either.
Houston had seven hits and three errors, losing its fifth consecutive game, 3-2 to the Mariners.
Iwakuma extended his streak of innings without an earned run to 28 2/3 -- he gave up an unearned run in the third -- while holding the Astros (22-43) to four hits over seven innings. The Mariners (28-37) got a Raul Ibanez solo home run and a pair of unearned runs to snap their own losing streak at two.
"One of the things we could hang our hat on was infield defense, and it let us down tonight," Astros manager Bo Porter said after the loss.
Two of Houston's hits came off Seattle closer Tom Wilhelmsen in the ninth. He gave up a leadoff single on an infield hit by J.D. Martinez, who came around to score on pinch hitter Carlos Corporan's two-out single. Mariners first baseman Kendrys Morales made an over-the-shoulder catch in foul territory to record the final out and give Wilhelmsen his 16th save of the season.
Seattle had nine hits while also taking advantage of Houston's defensive struggles. The Astros now have 47 errors on the season, matching the Los Angeles Angels for the most in the American League.
Houston starter Dallas Keuchel (3-3) gave up seven hits and two runs -- one earned -- while striking out six Mariners batters, but he didn't get much help from a Houston offense that has now failed to score more than two runs in each of the five games during the current losing streak.
"Our starting pitching has been outstanding," Porter said. "Even in this stretch (of losses), it's definitely not been our starting pitching."
Iwakuma (7-1) has now won his last five decisions and hasn't suffered a loss since April 23, when the Astros beat him 3-2. Monday's game dropped his season ERA to 1.79.
At Safeco Field, Iwakuma is now 3-0 with a 0.92 ERA this season.
"I feel very comfortable here and very used to it," he said through interpreter Antony Suzuki. "(Playing at home) helps me a lot."
The Mariners stranded 11 runners on base, including eight who were in scoring position.
An error on Mariners shortstop Brendan Ryan helped the Astros take a 1-0 lead in the third inning. Ryan missed a throw from pitcher Iwakuma on what appeared to be a routine fielder's choice -- and what likely would have started an inning-ending double play -- to put runners at first and third with one out. Jose Altuve's sacrifice fly scored Marwin Gonzalez from third for the first run of the game, an unearned run that ended Iwakuma's scoreless streak at 23 2/3 innings.
The Mariners tied the score 1-1 on an Raul Ibanez solo home run in the bottom of the fourth. It was Ibanez's 12th homer of the season, and his 10th in a 26-game span. It also was Seattle's first homer since June 5 -- a span of five games.
The Mariners added a run in the fifth, pulling ahead 2-1 on a throwing error from Houston third baseman Matt Dominguez. Kyle Seager ended up scoring from second base after Dominguez made a nice play to corral an infield hit by Kendrys Morales, but the throw to first was off-target, allowing Seager to round third and score easily.
Other than the unearned run in the third, Seattle's Iwakuma breezed through the first five innings. The Astros had just two hits off him while striking out six times in that stretch.
Houston's Carlos Pena led off the seventh with a double off Iwakuma, who then gave up his only walk of the game to Chris Carter to put two runners on with no one out. Iwakuma then got a strikeout and inning-ending double play to get out of that jam as the Mariners held their 2-1 lead.
"I was trying to slow the game down, to pitch with composure, and I was imagining getting a double play in that situation," Iwakuma said through Suzuki, adding that the pitch that led to Dominguez's double-play ground ball was a two-seam fastball.
Seattle took a 3-1 lead on a Michael Morse double in the bottom of the seventh. That came after Houston second baseman Altuve missed a throw from Dominguez at third on a potential double play.
NOTES: Morse (strained quad) was back in the lineup Monday, one day after sitting out a game to rest the lingering injury. He served as designated hitter while batting cleanup. ... Morales was back at first base Monday, despite the back stiffness that took him out of Saturday's game and forced him into a DH role Sunday. ... Before Monday night, the Astros' Keuchel had never started against the Mariners. ... Iwakuma's 23 2/3-inning scoreless streak was the eighth-longest streak in Mariners history. ... Ryan's third-inning error was his third in four games and his seventh of the season. Last year, Ryan had just nine errors in 141 games played. ... Astros LHP Wade LeBlanc, who was claimed off waivers from Miami on Saturday, made his Houston debut with one inning of work Monday. He gave up one hit and an unearned run.